lustre/mdc/mdc_locks.c

   1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
   2  * vim:expandtab:shiftwidth=8:tabstop=8:
   3  *
   4  * Copyright (C) 2001-2003 Cluster File Systems, Inc.
   5  *
   6  *   This file is part of Lustre, http://www.sf.net/projects/lustre/
   7  *
   8  *   Lustre is free software; you can redistribute it and/or
   9  *   modify it under the terms of version 2 of the GNU General Public
  10  *   License as published by the Free Software Foundation.
  11  *
  12  *   Lustre is distributed in the hope that it will be useful,
  13  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *   GNU General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU General Public License
  18  *   along with Lustre; if not, write to the Free Software
  19  *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #ifndef EXPORT_SYMTAB
  23 # define EXPORT_SYMTAB
  24 #endif
  25 #define DEBUG_SUBSYSTEM S_MDC
  26
  27 #ifdef __KERNEL__
  28 # include <linux/module.h>
  29 # include <linux/pagemap.h>
  30 # include <linux/miscdevice.h>
  31 # include <linux/init.h>
  32 #else
  33 # include <liblustre.h>
  34 #endif
  35
  36 #include <linux/obd_class.h>
  37 #include <linux/lustre_mds.h>
  38 #include <linux/lustre_dlm.h>
  39 #include <linux/lprocfs_status.h>
  40 #include <linux/lustre_acl.h>
  41 #include <linux/lustre_lite.h>
  42 #include "mdc_internal.h"
  43
  44 int it_disposition(struct lookup_intent *it, int flag)
  45 {
  46         return LUSTRE_IT(it)->it_disposition & flag;
  47 }
  48 EXPORT_SYMBOL(it_disposition);
  49
  50 void it_set_disposition(struct lookup_intent *it, int flag)
  51 {
  52         LUSTRE_IT(it)->it_disposition |= flag;
  53 }
  54 EXPORT_SYMBOL(it_set_disposition);
  55
  56 static void mdc_id2mdc_data(struct mdc_op_data *data,
  57                             struct lustre_id *f1,
  58                             struct lustre_id *f2,
  59                             const char *name,
  60                             int namelen, int mode)
  61 {
  62         LASSERT(data);
  63         LASSERT(f1);
  64
  65         data->id1 = *f1;
  66         if (f2)
  67                 data->id2 = *f2;
  68
  69         data->valid = 0;
  70         data->name = name;
  71         data->namelen = namelen;
  72         data->create_mode = mode;
  73         data->mod_time = LTIME_S(CURRENT_TIME);
  74 }
  75
  76 static int it_to_lock_mode(struct lookup_intent *it)
  77 {
  78         /* CREAT needs to be tested before open (both could be set) */
  79         if (it->it_op & IT_CREAT)
  80                 return LCK_PW;
  81         else if (it->it_op & (IT_READDIR | IT_GETATTR | IT_OPEN | IT_LOOKUP |
  82                               IT_CHDIR))
  83                 return LCK_PR;
  84
  85         LBUG();
  86         RETURN(-EINVAL);
  87 }
  88
  89 int it_open_error(int phase, struct lookup_intent *it)
  90 {
  91         if (it_disposition(it, DISP_OPEN_OPEN)) {
  92                 if (phase == DISP_OPEN_OPEN)
  93                         return LUSTRE_IT(it)->it_status;
  94                 else
  95                         return 0;
  96         }
  97
  98         if (it_disposition(it, DISP_OPEN_CREATE)) {
  99                 if (phase == DISP_OPEN_CREATE)
 100                         return LUSTRE_IT(it)->it_status;
 101                 else
 102                         return 0;
 103         }
 104
 105         if (it_disposition(it, DISP_LOOKUP_EXECD)) {
 106                 if (phase == DISP_LOOKUP_EXECD)
 107                         return LUSTRE_IT(it)->it_status;
 108                 else
 109                         return 0;
 110         }
 111
 112         if (it_disposition(it, DISP_IT_EXECD)) {
 113                 if (phase == DISP_IT_EXECD)
 114                         return LUSTRE_IT(it)->it_status;
 115                 else
 116                         return 0;
 117         }
 118         CERROR("it disp: %X, status: %d\n", LUSTRE_IT(it)->it_disposition,
 119                LUSTRE_IT(it)->it_status);
 120         LBUG();
 121         return 0;
 122 }
 123 EXPORT_SYMBOL(it_open_error);
 124
 125 /* this must be called on a lockh that is known to have a referenced lock */
 126 int mdc_set_lock_data(struct obd_export *exp, __u64 *l, void *data)
 127 {
 128         struct ldlm_lock *lock;
 129         struct lustre_handle *lockh = (struct lustre_handle *)l;
 130         ENTRY;
 131
 132         if (!*l) {
 133                 EXIT;
 134                 return 0;
 135         }
 136
 137         lock = ldlm_handle2lock(lockh);
 138
 139         LASSERT(lock != NULL);
 140         l_lock(&lock->l_resource->lr_namespace->ns_lock);
 141 #ifdef __KERNEL__
 142         if (lock->l_ast_data && lock->l_ast_data != data) {
 143                 struct inode *new_inode = data;
 144                 struct inode *old_inode = lock->l_ast_data;
 145                 LASSERTF(old_inode->i_state & I_FREEING,
 146                          "Found existing inode %p/%lu/%u state %lu in lock: "
 147                          "setting data to %p/%lu/%u\n", old_inode,
 148                          old_inode->i_ino, old_inode->i_generation,
 149                          old_inode->i_state, new_inode, new_inode->i_ino,
 150                          new_inode->i_generation);
 151         }
 152 #endif
 153         lock->l_ast_data = data;
 154         l_unlock(&lock->l_resource->lr_namespace->ns_lock);
 155         LDLM_LOCK_PUT(lock);
 156
 157         EXIT;
 158         return 0;
 159 }
 160 EXPORT_SYMBOL(mdc_set_lock_data);
 161
 162 int mdc_change_cbdata(struct obd_export *exp, struct lustre_id *id,
 163                       ldlm_iterator_t it, void *data)
 164 {
 165         struct ldlm_res_id res_id = { .name = {0} };
 166         ENTRY;
 167
 168         res_id.name[0] = id_fid(id);
 169         res_id.name[1] = id_group(id);
 170
 171         ldlm_change_cbdata(class_exp2obd(exp)->obd_namespace,
 172                            &res_id, it, data);
 173
 174         EXIT;
 175         return 0;
 176 }
 177
 178 /* We always reserve enough space in the reply packet for a stripe MD, because
 179  * we don't know in advance the file type. */
 180 int mdc_enqueue(struct obd_export *exp,
 181                 int lock_type,
 182                 struct lookup_intent *it,
 183                 int lock_mode,
 184                 struct mdc_op_data *data,
 185                 struct lustre_handle *lockh,
 186                 void *lmm,
 187                 int lmmsize,
 188                 ldlm_completion_callback cb_completion,
 189                 ldlm_blocking_callback cb_blocking,
 190                 void *cb_data)
 191 {
 192         struct ptlrpc_request *req;
 193         struct ldlm_res_id res_id = {
 194                 .name = {id_fid(&data->id1), id_group(&data->id1)}
 195         };
 196         struct obd_device *obddev = class_exp2obd(exp);
 197         ldlm_policy_data_t policy = { .l_inodebits = { MDS_INODELOCK_LOOKUP } };
 198         struct ldlm_intent *lit;
 199         struct ldlm_request *lockreq;
 200         struct ldlm_reply *dlm_rep;
 201         int reqsize[6] = {[MDS_REQ_SECDESC_OFF] = 0,
 202                           [MDS_REQ_INTENT_LOCKREQ_OFF] = sizeof(*lockreq),
 203                           [MDS_REQ_INTENT_IT_OFF] = sizeof(*lit)};
 204         int repsize[5] = {sizeof(struct ldlm_reply),
 205                           sizeof(struct mds_body),
 206                           obddev->u.cli.cl_max_mds_easize};
 207         int req_buffers = 3, reply_buffers = 0;
 208         int rc, flags = LDLM_FL_HAS_INTENT;
 209         void *eadata;
 210         unsigned long irqflags;
 211         ENTRY;
 212
 213 //        LDLM_DEBUG_NOLOCK("mdsintent=%s,name=%s,dir=%lu",
 214 //                          ldlm_it2str(it->it_op), it_name, it_inode->i_ino);
 215
 216         reqsize[0] = mdc_get_secdesc_size();
 217
 218         if (it->it_op & IT_OPEN) {
 219                 it->it_create_mode |= S_IFREG;
 220                 it->it_create_mode &= ~current->fs->umask;
 221
 222                 reqsize[req_buffers++] = sizeof(struct mds_rec_create);
 223                 reqsize[req_buffers++] = data->namelen + 1;
 224                 reqsize[req_buffers++] = obddev->u.cli.cl_max_mds_easize;
 225                 req = ptlrpc_prep_req(class_exp2cliimp(exp), LUSTRE_DLM_VERSION,
 226                                       LDLM_ENQUEUE, req_buffers, reqsize, NULL);
 227                 if (!req)
 228                         RETURN(-ENOMEM);
 229
 230                 spin_lock_irqsave (&req->rq_lock, irqflags);
 231                 req->rq_replay = 1;
 232                 spin_unlock_irqrestore (&req->rq_lock, irqflags);
 233
 234                 /* pack the intent */
 235                 lit = lustre_msg_buf(req->rq_reqmsg, MDS_REQ_INTENT_IT_OFF,
 236                                      sizeof (*lit));
 237                 lit->opc = (__u64)it->it_op;
 238
 239                 /* pack the intended request */
 240                 mdc_open_pack(req->rq_reqmsg, MDS_REQ_INTENT_REC_OFF, data,
 241                               it->it_create_mode, 0, it->it_flags,
 242                               lmm, lmmsize);
 243                 /* get ready for the reply */
 244                 repsize[3] = 4;
 245                 repsize[4] = xattr_acl_size(LL_ACL_MAX_ENTRIES);
 246                 reply_buffers = 5;
 247                 req->rq_replen = lustre_msg_size(5, repsize);
 248         } else if (it->it_op & (IT_GETATTR | IT_LOOKUP | IT_CHDIR)) {
 249                 __u64 valid = data->valid | OBD_MD_FLNOTOBD | OBD_MD_FLEASIZE |
 250                             OBD_MD_FLACL_ACCESS;
 251
 252                 reqsize[req_buffers++] = sizeof(struct mds_body);
 253                 reqsize[req_buffers++] = data->namelen + 1;
 254
 255                 if (it->it_op & IT_GETATTR)
 256                         policy.l_inodebits.bits = MDS_INODELOCK_UPDATE;
 257
 258                 req = ptlrpc_prep_req(class_exp2cliimp(exp), LUSTRE_DLM_VERSION,
 259                                       LDLM_ENQUEUE, req_buffers, reqsize, NULL);
 260
 261                 if (!req)
 262                         RETURN(-ENOMEM);
 263
 264                 /* pack the intent */
 265                 lit = lustre_msg_buf(req->rq_reqmsg, MDS_REQ_INTENT_IT_OFF,
 266                                      sizeof (*lit));
 267                 lit->opc = (__u64)it->it_op;
 268
 269                 /* pack the intended request */
 270                 mdc_getattr_pack(req->rq_reqmsg, MDS_REQ_INTENT_REC_OFF,
 271                                  valid, it->it_flags, data);
 272
 273                 /* get ready for the reply */
 274                 repsize[3] = 4;
 275                 repsize[4] = xattr_acl_size(LL_ACL_MAX_ENTRIES);
 276                 reply_buffers = 5;
 277                 req->rq_replen = lustre_msg_size(5, repsize);
 278         } else if (it->it_op == IT_READDIR) {
 279                 policy.l_inodebits.bits = MDS_INODELOCK_UPDATE;
 280                 req = ptlrpc_prep_req(class_exp2cliimp(exp), LUSTRE_DLM_VERSION,
 281                                       LDLM_ENQUEUE, 2, reqsize, NULL);
 282
 283                 if (!req)
 284                         RETURN(-ENOMEM);
 285                 /* get ready for the reply */
 286                 reply_buffers = 1;
 287                 req->rq_replen = lustre_msg_size(1, repsize);
 288         } else if (it->it_op == IT_UNLINK) {
 289                 reqsize[req_buffers++] = sizeof(struct mds_body);
 290                 policy.l_inodebits.bits = MDS_INODELOCK_UPDATE;
 291                 req = ptlrpc_prep_req(class_exp2cliimp(exp), LUSTRE_DLM_VERSION,
 292                                       LDLM_ENQUEUE, req_buffers, reqsize, NULL);
 293                 if (!req)
 294                         RETURN(-ENOMEM);
 295
 296                 /* pack the intended request */
 297                 mdc_getattr_pack(req->rq_reqmsg, MDS_REQ_INTENT_REC_OFF,
 298                                  0, 0, data);
 299
 300                 /* pack the intent */
 301                 lit = lustre_msg_buf(req->rq_reqmsg, MDS_REQ_INTENT_IT_OFF,
 302                                      sizeof (*lit));
 303                 lit->opc = (__u64)it->it_op;
 304
 305                 /* get ready for the reply */
 306                 reply_buffers = 3;
 307                 req->rq_replen = lustre_msg_size(3, repsize);
 308         } else {
 309                 LBUG();
 310                 RETURN(-EINVAL);
 311         }
 312
 313         mdc_pack_secdesc(req, reqsize[0]);
 314
 315         mdc_get_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
 316         rc = ldlm_cli_enqueue(exp, req, obddev->obd_namespace, res_id,
 317                               lock_type, &policy, lock_mode, &flags,cb_blocking,
 318                               cb_completion, NULL, cb_data, NULL, 0, NULL,
 319                               lockh);
 320         mdc_put_rpc_lock(obddev->u.cli.cl_rpc_lock, it);
 321
 322         /* Similarly, if we're going to replay this request, we don't want to
 323          * actually get a lock, just perform the intent. */
 324         if (req->rq_transno || req->rq_replay) {
 325                 lockreq = lustre_msg_buf(req->rq_reqmsg,
 326                                          MDS_REQ_INTENT_LOCKREQ_OFF,
 327                                          sizeof (*lockreq));
 328                 lockreq->lock_flags |= LDLM_FL_INTENT_ONLY;
 329         }
 330
 331         /* This can go when we're sure that this can never happen */
 332         LASSERT(rc != -ENOENT);
 333         if (rc == ELDLM_LOCK_ABORTED) {
 334                 lock_mode = 0;
 335                 memset(lockh, 0, sizeof(*lockh));
 336                 rc = 0;
 337         } else if (rc != 0) {
 338                 CERROR("ldlm_cli_enqueue: %d\n", rc);
 339                 LASSERT (rc < 0);
 340                 ptlrpc_req_finished(req);
 341                 RETURN(rc);
 342         } else { /* rc = 0 */
 343                 struct ldlm_lock *lock = ldlm_handle2lock(lockh);
 344                 LASSERT(lock);
 345
 346                 /* If the server gave us back a different lock mode, we should
 347                  * fix up our variables. */
 348                 if (lock->l_req_mode != lock_mode) {
 349                         ldlm_lock_addref(lockh, lock->l_req_mode);
 350                         ldlm_lock_decref(lockh, lock_mode);
 351                         lock_mode = lock->l_req_mode;
 352                 }
 353
 354                 ldlm_lock_allow_match(lock);
 355                 LDLM_LOCK_PUT(lock);
 356         }
 357
 358         dlm_rep = lustre_msg_buf(req->rq_repmsg, 0, sizeof (*dlm_rep));
 359         LASSERT(dlm_rep != NULL);           /* checked by ldlm_cli_enqueue() */
 360         LASSERT_REPSWABBED(req, 0);         /* swabbed by ldlm_cli_enqueue() */
 361
 362         LUSTRE_IT(it)->it_disposition = (int) dlm_rep->lock_policy_res1;
 363         LUSTRE_IT(it)->it_status = (int) dlm_rep->lock_policy_res2;
 364         LUSTRE_IT(it)->it_lock_mode = lock_mode;
 365         LUSTRE_IT(it)->it_data = req;
 366
 367         if (LUSTRE_IT(it)->it_status < 0 && req->rq_replay) {
 368                 LASSERT(req->rq_transno == 0);
 369                 /* Don't hold error requests for replay. */
 370                 spin_lock(&req->rq_lock);
 371                 req->rq_replay = 0;
 372                 spin_unlock(&req->rq_lock);
 373         }
 374
 375         DEBUG_REQ(D_RPCTRACE, req, "disposition: %x, status: %d",
 376                   LUSTRE_IT(it)->it_disposition, LUSTRE_IT(it)->it_status);
 377
 378         /* We know what to expect, so we do any byte flipping required here */
 379         LASSERT(reply_buffers == 5 || reply_buffers == 4 ||
 380                 reply_buffers == 3 || reply_buffers == 1);
 381         if (reply_buffers >= 3) {
 382                 struct mds_body *body;
 383
 384                 body = lustre_swab_repbuf(req, 1, sizeof (*body),
 385                                           lustre_swab_mds_body);
 386                 if (body == NULL) {
 387                         CERROR ("Can't swab mds_body\n");
 388                         RETURN (-EPROTO);
 389                 }
 390
 391                 if ((body->valid & OBD_MD_FLEASIZE) != 0) {
 392                         /* The eadata is opaque; just check that it is there.
 393                          * Eventually, obd_unpackmd() will check the contents */
 394                         eadata = lustre_swab_repbuf(req, 2, body->eadatasize,
 395                                                     NULL);
 396                         if (eadata == NULL) {
 397                                 CERROR ("Missing/short eadata\n");
 398                                 RETURN (-EPROTO);
 399                         }
 400                         if (it->it_op & IT_OPEN) {
 401                                 void *replayea;
 402
 403                                 replayea = lustre_msg_buf(req->rq_reqmsg,
 404                                                           MDS_REQ_INTENT_REC_OFF + 2,
 405                                                           body->eadatasize);
 406                                 LASSERT(replayea);
 407                                 memcpy(replayea, eadata, body->eadatasize);
 408
 409                                 LASSERT(req->rq_reqmsg->bufcount == 6);
 410                                 req->rq_reqmsg->buflens[5] = body->eadatasize;
 411                                 /* If this isn't the last buffer, we might
 412                                  * have to shift other data around. */
 413                         }
 414                 }
 415         }
 416
 417         RETURN(rc);
 418 }
 419 EXPORT_SYMBOL(mdc_enqueue);
 420
 421 /*
 422  * This long block is all about fixing up the lock and request state
 423  * so that it is correct as of the moment _before_ the operation was
 424  * applied; that way, the VFS will think that everything is normal and
 425  * call Lustre's regular VFS methods.
 426  *
 427  * If we're performing a creation, that means that unless the creation
 428  * failed with EEXIST, we should fake up a negative dentry.
 429  *
 430  * For everything else, we want to lookup to succeed.
 431  *
 432  * One additional note: if CREATE or OPEN succeeded, we add an extra
 433  * reference to the request because we need to keep it around until
 434  * ll_create/ll_open gets called.
 435  *
 436  * The server will return to us, in it_disposition, an indication of
 437  * exactly what d.lustre->it_status refers to.
 438  *
 439  * If DISP_OPEN_OPEN is set, then d.lustre->it_status refers to the open() call,
 440  * otherwise if DISP_OPEN_CREATE is set, then it status is the
 441  * creation failure mode.  In either case, one of DISP_LOOKUP_NEG or
 442  * DISP_LOOKUP_POS will be set, indicating whether the child lookup
 443  * was successful.
 444  *
 445  * Else, if DISP_LOOKUP_EXECD then d.lustre->it_status is the rc of the
 446  * child lookup.
 447  */
 448 int mdc_intent_lock(struct obd_export *exp, struct lustre_id *pid,
 449                     const char *name, int len, void *lmm, int lmmsize,
 450                     struct lustre_id *cid, struct lookup_intent *it,
 451                     int lookup_flags, struct ptlrpc_request **reqp,
 452                     ldlm_blocking_callback cb_blocking)
 453 {
 454         struct lustre_handle lockh;
 455         struct ptlrpc_request *request;
 456         struct mds_body *mds_body;
 457         struct lustre_handle old_lock;
 458         struct ldlm_lock *lock;
 459         int rc = 0;
 460         ENTRY;
 461         LASSERT(it);
 462
 463         CDEBUG(D_DLMTRACE, "name: %*s in obj "DLID4", intent: %s flags %#o\n",
 464                len, name, OLID4(pid), ldlm_it2str(it->it_op), it->it_flags);
 465
 466         if (cid && (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR ||
 467                     it->it_op == IT_CHDIR)) {
 468                 /* We could just return 1 immediately, but since we should only
 469                  * be called in revalidate_it if we already have a lock, let's
 470                  * verify that. */
 471                 struct ldlm_res_id res_id = {.name = {id_fid(cid),
 472                                                       id_group(cid)}};
 473                 struct lustre_handle lockh;
 474                 ldlm_policy_data_t policy;
 475                 int mode = LCK_PR;
 476
 477                 /* For the GETATTR case, ll_revalidate_it issues two separate
 478                    queries - for LOOKUP and for UPDATE lock because it cannot
 479                    check them together - we might have those two bits to be
 480                    present in two separate granted locks */
 481                 policy.l_inodebits.bits = (it->it_op == IT_GETATTR) ?
 482                         MDS_INODELOCK_UPDATE: MDS_INODELOCK_LOOKUP;
 483
 484                 mode = LCK_PR;
 485                 rc = ldlm_lock_match(exp->exp_obd->obd_namespace,
 486                                      LDLM_FL_BLOCK_GRANTED, &res_id,
 487                                      LDLM_IBITS, &policy, LCK_PR, &lockh);
 488                 if (!rc) {
 489                         mode = LCK_PW;
 490                         rc = ldlm_lock_match(exp->exp_obd->obd_namespace,
 491                                              LDLM_FL_BLOCK_GRANTED, &res_id,
 492                                              LDLM_IBITS, &policy, LCK_PW,
 493                                              &lockh);
 494                 }
 495                 if (rc) {
 496                         memcpy(&LUSTRE_IT(it)->it_lock_handle, &lockh,
 497                                sizeof(lockh));
 498                         LUSTRE_IT(it)->it_lock_mode = mode;
 499                 }
 500
 501                 /* Only return failure if it was not GETATTR by cid (from
 502                    inode_revalidate) */
 503                 if (rc || name)
 504                         RETURN(rc);
 505         }
 506
 507         /* lookup_it may be called only after revalidate_it has run, because
 508          * revalidate_it cannot return errors, only zero.  Returning zero causes
 509          * this call to lookup, which *can* return an error.
 510          *
 511          * We only want to execute the request associated with the intent one
 512          * time, however, so don't send the request again.  Instead, skip past
 513          * this and use the request from revalidate.  In this case, revalidate
 514          * never dropped its reference, so the refcounts are all OK */
 515         if (!it_disposition(it, DISP_ENQ_COMPLETE)) {
 516                 struct mdc_op_data *op_data;
 517
 518                 OBD_ALLOC(op_data, sizeof(*op_data));
 519                 if (op_data == NULL)
 520                         RETURN(-ENOMEM);
 521
 522                 mdc_id2mdc_data(op_data, pid, cid, name, len, 0);
 523
 524                 if (name != NULL)
 525                         op_data->valid |= OBD_MD_FID;
 526
 527                 rc = mdc_enqueue(exp, LDLM_IBITS, it, it_to_lock_mode(it),
 528                                  op_data, &lockh, lmm, lmmsize,
 529                                  ldlm_completion_ast, cb_blocking, NULL);
 530                 OBD_FREE(op_data, sizeof(*op_data));
 531                 if (rc < 0)
 532                         RETURN(rc);
 533
 534                 memcpy(&LUSTRE_IT(it)->it_lock_handle, &lockh, sizeof(lockh));
 535         }
 536         request = *reqp = LUSTRE_IT(it)->it_data;
 537         LASSERT(request != NULL);
 538
 539         /* If we're doing an IT_OPEN which did not result in an actual
 540          * successful open, then we need to remove the bit which saves this
 541          * request for unconditional replay.
 542          *
 543          * It's important that we do this first!  Otherwise we might exit the
 544          * function without doing so, and try to replay a failed create (bug
 545          * 3440) */
 546         if (it->it_op & IT_OPEN) {
 547                 if (!it_disposition(it, DISP_OPEN_OPEN) ||
 548                     LUSTRE_IT(it)->it_status != 0) {
 549                         unsigned long irqflags;
 550
 551                         spin_lock_irqsave(&request->rq_lock, irqflags);
 552                         request->rq_replay = 0;
 553                         spin_unlock_irqrestore(&request->rq_lock, irqflags);
 554                 }
 555         }
 556         if (!it_disposition(it, DISP_IT_EXECD)) {
 557                 /* The server failed before it even started executing the
 558                  * intent, i.e. because it couldn't unpack the request. */
 559                 LASSERT(LUSTRE_IT(it)->it_status != 0);
 560                 RETURN(LUSTRE_IT(it)->it_status);
 561         }
 562         rc = it_open_error(DISP_IT_EXECD, it);
 563         if (rc)
 564                 RETURN(rc);
 565
 566         mds_body = lustre_msg_buf(request->rq_repmsg, 1, sizeof(*mds_body));
 567         LASSERT(mds_body != NULL);      /* mdc_enqueue checked */
 568         LASSERT_REPSWABBED(request, 1); /* mdc_enqueue swabbed */
 569
 570         /* If we were revalidating a fid/name pair, mark the intent in case we
 571          * fail and get called again from lookup */
 572         if (cid != NULL) {
 573                 it_set_disposition(it, DISP_ENQ_COMPLETE);
 574                 /* Also: did we find the same inode? */
 575
 576                 /* we have to compare all the fields but type, because MDS can
 577                  * return fid/mds/ino/gen if inode lives on another MDS -bzzz */
 578                 if (!id_equal(cid, &mds_body->id1))
 579                         RETURN(-ESTALE);
 580         }
 581
 582         rc = it_open_error(DISP_LOOKUP_EXECD, it);
 583         if (rc)
 584                 RETURN(rc);
 585
 586         /*
 587          * keep requests around for the multiple phases of the call this shows
 588          * the DISP_XX must guarantee we make it into the call.
 589          */
 590         if (it_disposition(it, DISP_OPEN_CREATE) &&
 591             !it_open_error(DISP_OPEN_CREATE, it))
 592                 ptlrpc_request_addref(request); /* balanced in ll_create_node */
 593         if (it_disposition(it, DISP_OPEN_OPEN) &&
 594             !it_open_error(DISP_OPEN_OPEN, it))
 595                 ptlrpc_request_addref(request); /* balanced in ll_file_open */
 596
 597         if (it->it_op & IT_CREAT) {
 598                 /* XXX this belongs in ll_create_it */
 599         } else if (it->it_op == IT_OPEN) {
 600                 LASSERT(!it_disposition(it, DISP_OPEN_CREATE));
 601         } else {
 602                 LASSERT(it->it_op & (IT_GETATTR | IT_LOOKUP | IT_CHDIR));
 603         }
 604
 605         /*
 606          * if we already have a matching lock, then cancel the new one. We have
 607          * to set the data here instead of in mdc_enqueue, because we need to
 608          * use the child's inode as the l_ast_data to match, and that's not
 609          * available until intent_finish has performed the iget().)
 610          */
 611         lock = ldlm_handle2lock(&lockh);
 612         if (lock) {
 613                 ldlm_policy_data_t policy = lock->l_policy_data;
 614                 LDLM_DEBUG(lock, "matching against this");
 615                 LDLM_LOCK_PUT(lock);
 616
 617                 LASSERTF(id_fid(&mds_body->id1) == lock->l_resource->lr_name.name[0] &&
 618                          id_group(&mds_body->id1) == lock->l_resource->lr_name.name[1],
 619                          "Invalid lock is returned to client. Lock res_is: %lu/%lu, "
 620                          "response res_id: %lu/%lu.\n",
 621                          (unsigned long)lock->l_resource->lr_name.name[0],
 622                          (unsigned long)lock->l_resource->lr_name.name[1],
 623                          (unsigned long)id_fid(&mds_body->id1),
 624                          (unsigned long)id_group(&mds_body->id1));
 625
 626                 memcpy(&old_lock, &lockh, sizeof(lockh));
 627                 if (ldlm_lock_match(NULL, LDLM_FL_BLOCK_GRANTED, NULL,
 628                                     LDLM_IBITS, &policy, LCK_NL, &old_lock)) {
 629                         ldlm_lock_decref_and_cancel(&lockh,
 630                                                     LUSTRE_IT(it)->it_lock_mode);
 631                         memcpy(&lockh, &old_lock, sizeof(old_lock));
 632                         memcpy(&LUSTRE_IT(it)->it_lock_handle, &lockh,
 633                                sizeof(lockh));
 634                 }
 635         }
 636         CDEBUG(D_DENTRY, "D_IT dentry %*s intent: %s status %d disp %x rc %d\n",
 637                len, name, ldlm_it2str(it->it_op), LUSTRE_IT(it)->it_status,
 638                LUSTRE_IT(it)->it_disposition, rc);
 639
 640         RETURN(rc);
 641 }
 642 EXPORT_SYMBOL(mdc_intent_lock);